Recently, in a semiconductor device such as an MPU, its speed depends on a data transfer speed between a logic LSI such as a CPU or a GPU and a memory such as a DRAM. In order to increase the data transfer speed, it is known that the logic LSI is disposed below the DRAM, and the DRAM and the logic LSI are connected, for example, through an interposer that is a wiring interface. In such a semiconductor device, a heat radiating member is disposed above the DRAM for radiating heat of the DRAM and the logic LSI. Heat generated from the logic LSI such as a CPU or a GPU is transferred to the heat radiating member through the interposer and the DRAM and then radiated from the heat radiating member.